Quenching of the analyzing power for inclusive quasielastic (p→,p') scattering

Within the context of a nonrelativistic semiclassical distorted wave (SCDW) model, we demonstrate that the experimentally observed reduction of the inclusive quasielastic $^{208}\mathrm{Pb}$($\stackrel{\ensuremath{\rightarrow}}{p},{p}^{'}$) analyzing power relative to the value for free $NN$ scattering, at incident laboratory kinetic energies of 290 and 200 MeV and at the centroid of the quasielastic peak, is mainly attributed to nuclear medium modifications of the $NN$ effective interaction and also nuclear distortion effects on the scattering wave functions. In addition, the SCDW model also provides a satisfactory quantitative description of the unpolarized double differential cross section.